TALLAHASSEE -- A circuit court judge on Tuesday threw out Florida's ambitious school voucher program, an early setback for Gov. Jeb Bush in a legal battle expected to reach the state Supreme Court.

The ruling by Leon County Circuit Judge L. Ralph Smith Jr. says the nation's first statewide voucher program violates the Florida Constitution by providing taxpayer dollars for students to attend private schools.

The judge relied on a 1998 voter-approved revision to the Constitution, which declared education "through a system of free public schools" to be a paramount duty of the state.

The ruling allows 52 Escambia County students, now using vouchers to attend mostly Catholic schools, to finish the school year. But it prohibits the state from renewing the vouchers after June and from issuing them to other students.

Bush promised to appeal the decision to the Florida Supreme Court if necessary, pledging that the Escambia students would never return to the "failing" public schools they left. If he must, Bush said, he will pay their tuition.

"I'm going to ask all these guys to write me a check. We'll raise the money," said Bush, nodding toward Lt. Gov. Frank Brogan, Education Commissioner Tom Gallagher, House Speaker John Thrasher and other Republican leaders who flanked him at a news conference Tuesday.

The decision left some Pensacola parents confused and angry.

"I can tell you I'm disappointed, but I'm not surprised," said Andy Cameron, whose son Ray uses a voucher to attend fourth-grade at St. Michael's Catholic School.

"I pay taxes," Cameron said, "and my son was going to a public school that was a swillhole. It was not a very good school. This program was a good foundation for forcing the public schools to improve."

Dermita Merkman, whose daughter Jessica also attends St. Michael's on a voucher, agreed.

"I don't want her switching schools; she likes where she is and she's learning," Merkman said.

"I haven't said anything to her yet. Until I know something definite, I don't want to keep flip-flopping and getting her worried. I guess Mom will do all the worrying for now."

In his ruling, the judge agreed with Florida's two teacher unions, the NAACP, the Florida PTA and other groups that say the voucher program violates the constitutional revision approved by voters in 1998. Linda Lerner, a Pinellas County School Board member, is among the plaintiffs.

At the time it was proposed, opponents worried the revision would make it easy to sue the state for not providing adequate resources for Florida schoolchildren. No one predicted the amendment would be used to prohibit vouchers.

But that is exactly what the judge did, pointing to part of the revision that calls for a "system of free public schools." That wording, the judge ruled, "is, in effect, a prohibition on the Legislature to provide K-12 education in any other way."

Attorneys for the state argue that Florida already pays private schools to educate certain students, such as disabled students who need special services and students in some private programs for at-risk teens. Declaring vouchers to be unconstitutional could endanger those programs, the attorneys say.

The judge dismissed that argument, ruling that those students are different from voucher recipients because they have special needs that cannot be met in public schools.

Lawyers on both sides expect some legal maneuvering to unfold shortly. As predictable as the lawyerly wrangling is, the ultimate outcome remains uncertain.

The next step is an appeal of Judge Smith's ruling to the 1st District Court of Appeal, which Bush's attorneys said would be filed "within days." The appeal would trigger an automatic stay, which means the plan remains unchanged for now.

[AP photo]Teachers union head Pat L. Tornillo Jr. of FEA-United, at right with Maureen Dinnen, head of FTP-NEA, called Tuesday "a historic day."

But lawyers for the plaintiffs will try to undo that; they are promising to ask the judge to vacate the stay. If the judge agrees, that could temporarily suspend the voucher plan.

Of course, all that could change if a higher court disagrees with Smith's ruling. Attorneys on both sides said it is likely the appeals court will be asked to send the case directly to the state Supreme Court.

Escambia County school officials applauded the ruling and resolved to make it a smooth transition for children returning to the public schools.

"We always have concerns when children's education is interrupted," said Escambia school spokeswoman Barbara Frye. "It was the parents' choice to leave,and they understood -- or I hope they understood -- it was being challenged and that this could be taken away."

The voucher plan has been a political roller coaster from the start. During his 1998 campaign, Bush made clear his support for a statewide voucher plan but downplayed it as a small part of his education package. Then during his first legislative session, he fought hard to get passage of the voucher plan -- and the overall A+Education plan.

Within a matter of weeks, the grading plan was created -- quite hastily, critics said -- and the voucher plan was applied to two schools of predominantly poor and minority children in Pensacola

The schools -- A.A. Dixon Elementary and Spencer Bibbs Advanced Learning Academy -- were the only schools to get the state's lowest rating of "F" two years in a row. Parents at those schools had only a few weeks to decide whether to use a voucher and apply to a private school in the area.

This fall, students at 78 Florida schools that last year receivedF ratings could be eligible for vouchers. The final tally will depend on results of the Florida Comprehensive Assessment Test, which students took last month.

After the judge released his ruling Tuesday, teachers unions claimed victory and Democratic lawmakers chided Bush at hastily arranged news conferences in the Capitol.

At the same time, Bush was being interviewed by a correspondent for the ABC news program 20/20. The interview, about vouchers, had been scheduled before Tuesday's ruling, Bush said.

Democrats called on Bush to drop the voucher fight and focus on other efforts to improve public schools.

"We shouldn't have a government that has to be saved by the courts," said Rep. Lois J. Frankel, D-West Palm Beach.

Smith's decision could have national implications, said union leader Pat L. Tornillo Jr., president of the Florida Education Association. George W. Bush, Jeb Bush's brother and the presumptive Republican nominee for president, also supports school vouchers.

"It's a historic day, not just for Florida ... because all other states had their eye on Florida," Tornillo said.

"We stopped one brother. We're going to stop the other."

In Cleveland, where 3,700 children attend private schools on public dollars, a federal judge ruled that city's voucher program violates the constitutional separation of church and state. The Florida judge has not yet addressed that issue.

Most of the Cleveland children attend religious schools. The judge, however, allowed the children to remain in private schools while the state appeals that ruling.

The largest publicly funded voucher program is in Milwaukee, where 8,000 students attend private schools using public dollars. The U.S. Supreme Court refused to consider a challenge to the Milwaukee voucher program.

In the Florida lawsuit, "the goal is to prevent the thing from growing," said Ron Meyer, one of the lawyers challenging the voucher program. Meyer said he would not object if Bush arranged to have the Pensacola children attend private school with private money.

"I hope he does," Meyer said. "There's nothing wrong with these kids being where they are, in private school. The problem is using public dollars to pay their private school tuition."